which heads for a 408ci?

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754door

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I'am going to be starting to build a new motor for my car here pretty soon. And I wanted to know which would be the best set of heads to make 500hp to 525hp NA with a solid roller cam. I was thinking the comp with the .564/.570 lift. Was thinking ported eddys or ported magnums from hughes or porting a set myself since I started up here in Bemidji at a engine machinist school.

Just wanted to see what you guys thought would be the best for the money.
 
What length is the connecting rods? As piston speed determines the amount of cylinder head that is needed, and is this going to be street only or some racing also?
 
754door said:
I'am going to be starting to build a new motor for my car here pretty soon. And I wanted to know which would be the best set of heads to make 500hp to 525hp NA with a solid roller cam. I was thinking the comp with the .564/.570 lift. Was thinking ported eddys or ported magnums from hughes or porting a set myself since I started up here in Bemidji at a engine machinist school.

Just wanted to see what you guys thought would be the best for the money.
Click to expand...

Best bang for the buck..Edelbrocks of coarse,i've got a set of mildly ported(as in just cleaned-up the ports and blended the bowls) on top of my 416 making a dynoed 519 h.p. and thats with a hyd cam smaller then the solid you want to run..best of 11.02 so far..
 
i had a set of edelbrocks atop my 416, .585 lift ultradyne solid cam and 11.5:1comp, and i was disapointed. 11.8 was all i could muster out of it. I put a set of 1976 casting w-2 race heads with 2.08 long valves and the car went 11.5 right out of the box. this is in a 3700 lbs challenger with a 4speed. the w-2's are a way better performing than the eddy's. even when i built my motor muscle motors told me i'd have to spend another 1500 on the eddy's just to get them to flow enough. keep in mind this is canadian dollars, so for the heads it was 2000.00 and for porting it was 1500.00 = 3500.00. this is just my opinion. there are alot of good performing heads out there but if your going to have to spend 3500.00 on a set of eddy's why not just buy a set of indy's and be done with it, those heads are basically taloired for a stroker smallblock as are a set of prepped w-2's.
 
INDY out of the box, using a fairly small flat tappet cam .
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I think the length of the rods would be 6.123. What kind of cfm would I need to get a set of eddys to to make that kind of power. I was thinking what like 280cfm at like .600lift. We have a flow bench at the school that I know how to use and we are soon getting a wet flow bench from joe mondello. It will be street/strip. What type of springs would I need for a solid roller only revving to about 6000rpm? Something like beehives maybe.
 
Find out what the matched springs are for the Comp cam and if they'll be a problem swapping them on to a set of the Edel. heads which I wouldn't use for this type of build and then cross ref. them with some that would fit better on the head.

Nothing wrong with porting heads, the heads you have, but to purchase Edelbrock heads and then port them isn't what I would call the best move. Being that your not paying for the porting, per-say since your in school for this type of thing, I'd call it a learning exper. on porting a head. But still not the best move.

The Edel. head can do a 500 HP engine without porting if all else is in line.
The Edelbrock web site used to have and may still do have the section on Mag. stories were a 360 (@ .070 overbore) pulled 500+ hp with a Comp Hyd. 308 cam. I'd read the story first.
 
couldn't find the article. But I have already started porting a 318 head for my head porting class. It flowed 177cfm at .500lift stock on the intake. And I will be flowing it agian on tuesday to see what I picked up I bowl blended it, some short side radius work and I tear droped the guide all the way around so there is a nice curve all the way around looks pretty nice. I still have some more smoothing out to do but it is getting there. If I could the picture of my phone on to here I would. I will take a digital pic of it on monday and post it.
 
Yea, I couldn't find it ethier. I'm forgetting who built the engine. Buty the heads ended up fully ported to make the mark.
the used to have a link on the side bar, "Mag articles"
It's gone now.
 
if you are able to port the heads yourself go the the econo w-2's. there was an article in the nov. 2001 edition of mopar muscle that blew me away on how good these heads will actually flow. they will outperform the eddy's hands down. this article shows how the w-2 outperforms practcally every aftermarket aluminum chevy head whether as cast,cnc ported, or running much bigger valves. these heads even outperformed a fully ported 460 ford aluminum head with 2.25 intake valves ! i have the flow chart for these heads and the article that they did on them i just don't know how to paste it to this page. anyways mopar muscle did an another article building a 408 stroker and when using these heads the made 607 hp at 6600 rpm with the smallest roller in comps catalog and a tunnel ram setup. they also made 583 hp with a m1 single plane and an 850 dp holley. these numbers are very impressive. the article was called 360 a-bomb and the articles started in the january 2002 issue. i can try emailing you the w2 article if you would like.
 
but where can I buy econo w2s. I have looked on summit but they just have standard w2s. Also it would be alot more work need special intake rockers and headers. Which I don't really want to do. What is the max cfm any one ever got of a 596 head or j head. If I could port my head to support 500hp with comp XR274R solid roller cam than I would. Will see what I can get out of this 318 head.

A kid In my class said he got 244cfm out of 993 chevy head with a bowl blend and some work on the short side radius. it flowed like 200cfm stock and now with just a little work its up with edelbrock capabiltites. I don't beleive a word this kid says.
 
Don't worry about what he said and don't worry about peak flow. Look for best area under curve and you'll do better on the street or strip with less because the Chevy head might not have jack down low.

Last set of W-2 from MoPar Performance I have seen were OK for use with regular heders with it's dual tapped exhaust holes for headers.
The only weird part in the head not stock on regular car but the one year only 340 - 6 pak engines is the off set rocker. Everything else is stock capable.
Though since your going to make power, toss the stock stuff for a good set of material. It'll be worth it in the long run.
 
i couldn't find the article. anyways mopar performance has the part number for those econo heads which are just the standard heads anyways. it can be a pricey swap, but if you get the econo heads it has a dual pattern for standard headers (you'll just have to port match the header flange). intake manifold is easy. the rocker assemblies is what costs the bucks but if your going to buy all new stuff anyways whats the diff. i have a set of 2" a body headers for the w2's if you ever want to go that route , and i'm sure we could work out some sort of deal if you ever needed them
 
I will probably go with a set of ported edelbrocks either ported by me or by hughes engines. And get springs that match the solid roller cam.
 
This is my personal opinion on how to achieve what you are wanting at the lowest price with the best equipment.

Use Magnum aluminum heads, either Eddy's or Mopar Performance. With these heads you should be able to get 275 cfm of flow at that cam lift, more than enough to support the horsepower you are looking to get. The bonus here is you can use Chevy aluminum 1.6 rockers (cheap, comparatively), and you lose weight off the front end as well. They are also better for running pump gas. Go ahead and clean them up good, don't touch the floor of the port though unless you really know what you are doing.
 
That car craft build is'nt impressive,they got 600 h.p. from a stroker running ported w-2 heads,and a tunnel ram with dual quads.big deal...
 
That link would not be the one I was after. They have a titled write up called "A bomn". I don't think thats the one.
I'll look in my archives later for the meat and potatos of it.
 
Do I have to do anything special to put a solid roller in a 72 360 block. Like bush the lifter bores.
 
754door said:
I think the length of the rods would be 6.123. What kind of cfm would I need to get a set of eddys to to make that kind of power. I was thinking what like 280cfm at like .600lift. We have a flow bench at the school that I know how to use and we are soon getting a wet flow bench from joe mondello. It will be street/strip. What type of springs would I need for a solid roller only revving to about 6000rpm? Something like beehives maybe.
Click to expand...

For your rod length from my calulations and piston speed tell me that you would need 240 cc's of port volume and 290 cfm's at .600 lift. To efficiently feed the engine. But once again it's just my opinion.
 
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